View source for Natural environment

{{Short description|Living and non-living things on Earth}}
{{Redirect|Natural force|the music album|Natural Force{{!}}''Natural Force''}}

[[File:Hopetoun falls.jpg|thumb|right|[[Land management]] has preserved the natural characteristics of [[Hopetoun Falls]], [[Australia]] while allowing ample access for visitors.]]
[[File:Sahara satellite hires.jpg|thumb|An image of the [[Sahara|Sahara Desert]] from satellite. It is the world's largest hot desert and third-largest desert after the [[polar desert]]s.]]

The '''natural environment''' or '''natural world''' encompasses all [[life|biotic]] and [[abiotic component|abiotic]] things occurring [[nature|naturally]], meaning in this case not [[artificiality|artificial]]. The term is most often applied to [[Earth]] or some parts of Earth. This environment encompasses the interaction of all living [[species]], [[climate]], weather and natural resources that affect human survival and economic activity.<ref>{{cite journal|last1=Johnson|first1=D. L.|first2=S. H.|last2=Ambrose|first3=T. J.|last3=Bassett|first4=M. L.|last4=Bowen|first5=D. E.|last5=Crummey|first6=J. S.|last6=Isaacson|first7=D. N.|last7=Johnson|first8=P.|last8=Lamb|first9=M.|last9=Saul|first10=A. E.|last10=Winter-Nelson|year=1997|title=Meanings of Environmental Terms|journal=Journal of Environmental Quality|volume=26|issue=3|pages=581–589|doi=10.2134/jeq1997.00472425002600030002x|bibcode=1997JEnvQ..26..581J }}</ref>
The concept of the ''natural environment'' can be distinguished as components:
* Complete [[ecological unit]]s that function as natural systems without massive civilized human intervention, including all vegetation, [[microorganism]]s, [[soil]], [[rock (geology)|rocks]], plateaus, mountains, the [[atmosphere of Earth|atmosphere]] and [[list of natural phenomena|natural phenomena]] that occur within their boundaries and their nature.
* Universal [[natural resource]]s and [[phenomenon|physical phenomena]] that lack clear-cut boundaries, such as air, water and climate, as well as [[energy]], [[radiation]], [[electric charge]] and [[magnetism]], not originating from civilized human actions.

In contrast to the natural environment is the [[built environment]]. Built environments are where humans have fundamentally transformed landscapes such as urban settings and agricultural [[land development|land conversion]], the natural environment is greatly changed into a simplified human environment. Even acts which seem less extreme, such as building a mud [[hut]] or a [[photovoltaic system]] in the [[desert]], the modified environment becomes an artificial one. Though many animals build things to provide a better environment for themselves, they are not human, hence [[beaver dam]]s and the works of [[mound-building termites]] are thought of as natural.

People cannot find ''absolutely natural'' environments on Earth, naturalness usually varies in a continuum, from 100% natural in one extreme to 0% natural in the other. The massive environmental changes of humanity in the [[Anthropocene]] have fundamentally effected all natural environments including: [[climate change]], [[biodiversity loss]] and pollution from [[Plastic pollution|plastic]] and [[Pollution|other chemicals]] in the [[Air pollution|air]] and [[Water pollution|water]]. More precisely, we can consider the different aspects or components of an environment, and see that their degree of naturalness is not uniform.<ref>{{cite book |first=Donald |last=Symons |title=The Evolution of Human Sexuality |page=[https://archive.org/details/evolutionofhuman00dona/page/31 31] |publisher=Oxford University Press |year=1979 |location=New York |isbn=0-19-502535-0 |url=https://archive.org/details/evolutionofhuman00dona/page/31 }}</ref> If, for instance, in an agricultural field, the [[mineralogy|mineralogic composition]] and the [[soil structure|structure]] of its soil are similar to those of an undisturbed forest soil, but the structure is quite different.

== Composition ==
{{Main|Earth science}}
[[File:Jordens inre-numbers.svg|thumb|[[Earth]]'s layered structure: (1) inner core; (2) outer core; (3) lower mantle; (4) [[upper mantle (Earth)|upper mantle]]; (5) lithosphere; (6) crust]]

Earth science generally recognizes four spheres, the [[lithosphere]], the [[hydrosphere]], the [[atmosphere]] and the [[biosphere]]<ref name="wheeling">
[http://www2.cet.edu/ete/hilk4/intro/spheres.html Earth's Spheres] {{webarchive|url=https://web.archive.org/web/20070831022404/http://www2.cet.edu/ete/hilk4/intro/spheres.html |date=2007-08-31 }}. Wheeling Jesuit University/NASA Classroom of the Future. Retrieved November 11, 2007.</ref> as correspondent to [[Rock (geology)|rocks]], [[water]], [[air]] and [[life]] respectively. Some scientists include as part of the spheres of the Earth, the [[cryosphere]] (corresponding to [[ice]]) as a distinct portion of the hydrosphere, as well as the [[pedosphere]] (to [[soil]]) as an active and intermixed sphere. [[Earth science]] (also known as geoscience, the geographical sciences or the Earth Sciences), is an all-embracing term for the [[science]]s related to the planet [[Earth (planet)|Earth]].<ref>{{Cite web |url=https://geology.buzz/threads/what-is-earth-science.4/ |title=What is Earth Science? {{!}} Geology Buzz |access-date=2021-12-24 |archive-date=2021-12-24 |archive-url=https://web.archive.org/web/20211224172832/https://geology.buzz/threads/what-is-earth-science.4/ |url-status=live }}</ref> There are four major [[discipline]]s in earth sciences, namely [[geography]], [[geology]], [[geophysics]] and [[geodesy]]. These major disciplines use [[physics]], [[chemistry]], [[biology]], [[chronology]] and [[mathematics]] to build a qualitative and quantitative understanding of the principal areas or ''[[Outline of Earth sciences#Earth's spheres|spheres]]'' of Earth.

{{clear}}

==Geological activity==
{{Main|Geology}}
The [[Crust (geology)#Earth's crust|Earth's crust]] or [[lithosphere]], is the outermost solid surface of the planet and is chemically, physically and mechanically different from underlying [[Mantle (geology)|mantle]]. It has been generated greatly by [[igneous]] processes in which [[magma]] cools and solidifies to form solid rock. Beneath the lithosphere lies the mantle which is heated by the [[radioactive decay|decay]] of [[radioactive element]]s. The mantle though solid is in a state of [[rheid|rheic]] [[convection]]. This convection process causes the lithospheric plates to move, albeit slowly. The resulting process is known as [[plate tectonics]]. [[Volcanoes]] result primarily from the melting of [[Subduction|subducted]] crust material or of rising mantle at [[mid-ocean ridge]]s and [[mantle plume]]s.

==Water on Earth==
[[File:Blue Linckia Starfish.JPG|thumb|upright|[[Coral reef]]s have significant marine [[biodiversity]].]]
Most water is found in various kinds of natural [[body of water]].

=== Oceans ===
{{Main|Ocean}}
An ocean is a major body of [[Seawater|saline water]] and a component of the hydrosphere. Approximately 71% of the [[surface of the Earth]] (an area of some 362 million square kilometers) is covered by ocean, a [[World Ocean|continuous body of water]] that is customarily divided into several principal oceans and smaller [[sea]]s. More than half of this area is over 3,000 meters (9,800&nbsp;ft) deep. Average oceanic [[salinity]] is around 35 [[parts per thousand]] (ppt) (3.5%), and nearly all seawater has a salinity in the range of 30 to 38 ppt. Though generally recognized as several separate oceans, these waters comprise one global, interconnected body of salt water often referred to as the [[World Ocean]] or global ocean.<ref>"{{cite web |url=http://www.pagejaffna.com/ |title=Page Jaffna &#124; Srilanka's Top Tamil Online News Paper |access-date=2012-07-15 |url-status=dead |archive-url=https://web.archive.org/web/20120714233027/http://www.pagejaffna.com/ |archive-date=2012-07-14 }}". ''The Columbia Encyclopedia.'' 2002. New York: Columbia University Press</ref><ref name="UNAoO">"[http://www.oceansatlas.com/unatlas/about/physicalandchemicalproperties/background/seemore1.html Distribution of land and water on the planet] {{webarchive |url=https://web.archive.org/web/20080531103749/http://www.oceansatlas.com/unatlas/about/physicalandchemicalproperties/background/seemore1.html |date=May 31, 2008 }}". [http://www.oceansatlas.com/ UN Atlas of the Oceans] {{webarchive |url=https://web.archive.org/web/20080915105349/http://www.oceansatlas.com/ |date=September 15, 2008 }}</ref> The deep [[seabed]]s are more than half the Earth's surface, and are among the least-modified natural environments. The major oceanic divisions are defined in part by the [[continent]]s, various [[archipelago]]s and other criteria, these divisions are : (in descending order of size) the [[Pacific Ocean]], the [[Atlantic Ocean]], the [[Indian Ocean]], the [[Southern Ocean]] and the [[Arctic Ocean]].

=== Rivers ===
{{Main|River}}
A river is a natural [[watercourse]],<ref>[http://www.merriam-webster.com/dictionary/river River {definition}] {{Webarchive|url=https://web.archive.org/web/20100221200545/http://www.merriam-webster.com/dictionary/river |date=2010-02-21 }} from Merriam-Webster. Accessed February 2010.</ref> usually [[freshwater]], flowing toward an [[ocean]], a [[lake]], a [[sea]] or another river. A few rivers simply flow into the ground and dry up completely without reaching another body of water.
[[File:Hawaii Creek.jpg|thumb|left|Rocky [[stream]] in the U.S. state of [[Hawaii]]]]

The water in a river is usually in a [[channel (geography)|channel]], made up of a [[stream bed]] between [[stream bank|banks]]. In larger rivers there is often also a wider [[floodplain]] shaped by waters over-topping the channel. Flood plains may be very wide in relation to the size of the river channel. Rivers are a part of the [[hydrological cycle]]. Water within a river is generally collected from [[Precipitation (meteorology)|precipitation]] through [[surface runoff]], [[groundwater recharge]], [[spring (hydrosphere)|springs]] and the release of water stored in [[glacier]]s and snowpacks.

Small rivers may also be called by several other names, including [[stream]], creek and brook. Their [[Current (stream)|current]] is confined within a [[stream bed|bed]] and [[stream bank]]s. Streams play an important [[wildlife corridor|corridor]] role in connecting [[Habitat fragmentation|fragmented habitats]] and thus in conserving [[biodiversity]]. The study of streams and waterways in general is known as ''surface [[hydrology]]''.<ref>{{cite web |url=http://ga.water.usgs.gov/edu/hydrology.html/ |url-status=dead |archive-url=https://web.archive.org/web/20120427204108/http://ga.water.usgs.gov/edu/hydrology.html |title=What is hydrology and what do hydrologists do? |archive-date=April 27, 2012 |publisher=United States Geological Survey |access-date=July 27, 2021}}</ref>
{{Further|Stream}}

=== Lakes ===
[[File:LAGO LACAR.JPG|thumb|right|[[Lácar Lake]], of [[glacier|glacial]] origin, in the {{province|Neuquén|Argentina}}]]

{{Main|Lake}}

A lake (from Latin ''lacus'') is a [[terrain feature]], a body of water that is localized to the bottom of [[Depression (geology)|basin]]. A body of water is considered a lake when it is inland, is not part of an [[ocean]] and is larger and deeper than a [[pond]].<ref>{{cite web
|url=https://www.britannica.com/EBchecked/topic/328083/lake
|author=Britannica Online
|access-date=2008-06-25
|title=Lake (physical feature)
|quote=[a Lake is] any relatively large body of slowly moving or standing water that occupies an inland basin of appreciable size. Definitions that precisely distinguish lakes, ponds, swamps, and even rivers and other bodies of nonoceanic water are not established. It may be said, however, that rivers and streams are relatively fast-moving; marshes and swamps contain relatively large quantities of grasses, trees, or shrubs; and ponds are relatively small in comparison to lakes. Geologically defined, lakes are temporary bodies of water.
|archive-date=2008-06-11
|archive-url=https://web.archive.org/web/20080611194244/https://www.britannica.com/EBchecked/topic/328083/lake
|url-status=live
}}</ref><ref>{{cite web
|title=Dictionary.com definition
|access-date=2008-06-25
|url=http://dictionary.reference.com/browse/lake
|quote=a body of fresh or salt water of considerable size, surrounded by land.
|archive-date=2008-06-17
|archive-url=https://web.archive.org/web/20080617185933/http://dictionary.reference.com/browse/Lake
|url-status=live
}}</ref>
[[File:Everglades Park swamp.JPG|thumb|left|A [[swamp]] area in [[Everglades National Park]], [[Florida]], [[US]]]]

Natural lakes on Earth are generally found in [[mountain]]ous areas, [[rift zone]]s and areas with ongoing or recent [[glacier|glaciation]]. Other lakes are found in [[endorheic basin]]s or along the courses of mature rivers. In some parts of the world, there are many lakes because of chaotic drainage patterns left over from the [[Last Glacial Period|last ice age]]. All lakes are temporary over geologic time scales, as they will slowly fill in with sediments or spill out of the basin containing them.

==== Ponds ====
{{Main|Pond}}
A pond is a [[body of water|body]] of [[Water stagnation|standing water]], either natural or human-made, that is usually smaller than a [[lake]]. A wide variety of human-made bodies of water are classified as ponds, including [[water garden]]s designed for aesthetic ornamentation, [[fish pond]]s designed for commercial fish breeding and [[solar pond]]s designed to store thermal energy. Ponds and lakes are distinguished from streams by their [[Flow velocity|current speed]]. While currents in streams are easily observed, ponds and lakes possess thermally driven micro-currents and moderate wind-driven currents. These features distinguish a pond from many other aquatic terrain features, such as [[stream pool]]s and [[tide pool]]s.

=== Human impact on water ===
Humans impact the water in different ways such as modifying rivers (through [[dam]]s and [[Channelization (rivers)|stream channelization]]), [[urbanization]] and [[deforestation]]. These impact lake levels, groundwater conditions, water pollution, thermal pollution, and [[marine pollution]]. Humans modify rivers by using direct channel manipulation.<ref name=Goudie>{{Cite book|title=The Human Impact on the Natural Environment|last=Goudie|first=Andrew|publisher=This MIT Press|year=2000|isbn=0-262-57138-2|location=Cambridge, Massachusetts|pages=[https://archive.org/details/humanimpactonn00goud/page/203 203–239]|url=https://archive.org/details/humanimpactonn00goud/page/203}}</ref> We build dams and reservoirs and manipulate the direction of the rivers and water path. Dams can usefully create reservoirs and hydroelectric power. However, reservoirs and dams may negatively impact the environment and wildlife. Dams stop fish migration and the movement of organisms downstream. Urbanization affects the environment because of deforestation and changing lake levels, groundwater conditions, etc. Deforestation and urbanization go hand in hand. Deforestation may cause flooding, declining stream flow and changes in riverside vegetation. The changing vegetation occurs because when trees cannot get adequate water they start to deteriorate, leading to a decreased food supply for the wildlife in an area.<ref name=Goudie/>

== Atmosphere, climate and weather ==
[[File:Top of Atmosphere.jpg|thumb|right|Atmospheric gases [[Rayleigh scattering|scatter blue light more than other wavelengths]], creating a blue [[Halo (optical phenomenon)|halo]] when seen from space.]]
[[File:Troposphere CIMG1853.JPG|thumb|right|A view of Earth's [[troposphere]] from an [[airplane]]]]
[[File:Lightnings sequence 2 animation-wcag.gif|thumb|[[Lightning]] is an [[Earth's atmosphere|atmospheric]] discharge of [[electricity]] accompanied by [[thunder]], which occurs during [[thunderstorm]]s and certain other natural conditions.<ref name="noaa1">{{cite web|url=http://www.ngdc.noaa.gov/seg/hazard/stratoguide/galunfeat.html|title=Galgunggung, Indonesia: Volcanic Lightning|access-date=September 21, 2007|publisher=Teachers Guide to Stratovolcanoes of the World |work=National Geophysical Data Center – NOAA |archive-date=December 25, 2007|archive-url=https://web.archive.org/web/20071225203407/http://www.ngdc.noaa.gov/seg/hazard/stratoguide/galunfeat.html|url-status=dead}}</ref>]]

The atmosphere of the Earth serves as a key factor in sustaining the planetary ecosystem. The thin layer of [[gas]]es that envelops the Earth is held in place by the planet's gravity. Dry [[air]] consists of 78% [[nitrogen]], 21% [[oxygen]], 1% [[argon]], [[inert gases]] and [[carbon dioxide]]. The remaining gases are often referred to as trace gases.<ref>{{cite web |author=Joe Buchdahl |url=http://www.ace.mmu.ac.uk/eae/Atmosphere/Older/Trace_Gases.html |title=Trace Gases |work=Encyclopedia of the Atmospheric Environment |publisher=Atmosphere, Climate & Environment Information Programme |access-date=2013-03-09 |url-status=dead |archive-url=https://web.archive.org/web/20101009044345/http://www.ace.mmu.ac.uk/eae/atmosphere/older/Trace_Gases.html |archive-date=2010-10-09 }}</ref> The atmosphere includes [[greenhouse gas]]es such as carbon dioxide, methane, [[nitrous oxide]] and ozone. Filtered air includes trace amounts of many other [[chemical compound]]s. Air also contains a variable amount of [[water vapor]] and [[Suspension (chemistry)|suspensions]] of water droplets and [[ice]] crystals seen as [[cloud]]s. Many natural substances may be present in tiny amounts in an unfiltered air sample, including [[dust]], [[pollen]] and [[spores]], [[sea spray]], [[volcanic ash]] and [[meteoroid]]s. Various industrial [[pollutant]]s also may be present, such as [[chlorine]] (elementary or in compounds), [[fluorine]] compounds, elemental [[Mercury (element)|mercury]], and [[sulphur]] compounds such as [[sulphur dioxide]] (SO<sub>2</sub>).

The [[ozone layer]] of the Earth's atmosphere plays an important role in reducing the amount of [[ultraviolet]] (UV) radiation that reaches the surface. As [[DNA]] is readily damaged by UV light, this serves to protect life at the surface. The atmosphere also retains heat during the night, thereby reducing the daily temperature extremes.

===Layers of the atmosphere===
{{Main|Earth's atmosphere}}

====Principal layers====
Earth's atmosphere can be divided into five main layers. These layers are mainly determined by whether temperature increases or decreases with altitude. From highest to lowest, these layers are:
* [[Exosphere]]: The outermost layer of Earth's atmosphere extends from the exobase upward, mainly composed of [[hydrogen]] and [[helium]].
* [[Thermosphere]]: The top of the thermosphere is the bottom of the exosphere, called the [[exobase]]. Its height varies with solar activity and ranges from about {{convert|350|-|800|km|mi ft|abbr=on}}. The [[International Space Station]] orbits in this layer, between {{convert|320|and|380|km|mi|abbr=on}}. In another way, the thermosphere is Earth's second highest atmospheric layer, extending from approximately 260,000 feet at the mesopause to the thermopause at altitudes ranging from 1,600,000 to 3,300,000 feet.<ref>{{Cite web |title=Thermosphere - an overview {{!}} ScienceDirect Topics |url=https://www.sciencedirect.com/topics/earth-and-planetary-sciences/thermosphere |access-date=2023-07-25 |website=www.sciencedirect.com}}</ref>
* [[Mesosphere]]: The mesosphere extends from the stratopause to {{convert|80|-|85|km|mi ft|abbr=on}}. It is the layer where most [[meteor]]s burn up upon entering the atmosphere.<ref>{{Cite web |title=Mesosphere - an overview {{!}} ScienceDirect Topics |url=https://www.sciencedirect.com/topics/earth-and-planetary-sciences/mesosphere |access-date=2023-07-25 |website=www.sciencedirect.com}}</ref><ref>{{Cite web |title=Mesosphere {{!}} NASA Space Place – NASA Science for Kids |url=https://spaceplace.nasa.gov/mesosphere/en/ |access-date=2023-07-25 |website=spaceplace.nasa.gov}}</ref>
* [[Stratosphere]]: The stratosphere extends from the tropopause to about {{convert|51|km|mi ft|abbr=on}}. The [[stratopause]], which is the boundary between the stratosphere and mesosphere, typically is at {{convert|50|to|55|km|mi ft|abbr=on}}.
* [[Troposphere]]: The troposphere begins at the surface and extends to between {{convert|7|km|ft|abbr=on}} at the poles and {{convert|17|km|ft|abbr=on}} at the equator, with some variation due to weather. The troposphere is mostly heated by transfer of energy from the surface, so on average the lowest part of the troposphere is warmest and temperature decreases with altitude. The [[tropopause]] is the boundary between the troposphere and stratosphere.

; Other layers
Within the five principal layers determined by temperature there are several layers determined by other properties.
* The [[ozone layer]] is contained within the stratosphere. It is mainly located in the lower portion of the stratosphere from about {{convert|15|-|35|km|mi ft|abbr=on}}, though the thickness varies seasonally and geographically. About 90% of the ozone in our atmosphere is contained in the stratosphere.
* The [[ionosphere]]: The part of the atmosphere that is ionized by solar radiation, stretches from {{convert|50|to|1000|km|mi ft|abbr=on}} and typically overlaps both the exosphere and the thermosphere. It forms the inner edge of the magnetosphere.
* The [[homosphere]] and [[heterosphere]]: The homosphere includes the troposphere, stratosphere and mesosphere. The upper part of the heterosphere is composed almost completely of hydrogen, the lightest element.
* The [[planetary boundary layer]] is the part of the troposphere that is nearest the Earth's surface and is directly affected by it, mainly through [[turbulence|turbulent diffusion]].

====Effects of global warming====
[[File:Gletscherschmelze.jpg|thumb|left|The retreat of glaciers since 1850 of [[Aletsch Glacier]] in the [[Swiss Alps]] (situation in 1979, 1991 and 2002), due to [[global warming]]]]
{{Main|Effects of global warming}}

The dangers of [[global warming]] are being increasingly studied by a wide global consortium of scientists.<ref>{{Cite web|url=https://www.isro.gov.in/update/03-jun-2016/world%E2%80%99s-space-agencies-unite-to-face-climate-challenge|title=World's Space Agencies Unite To Face The Climate Challenge – ISRO|website=www.isro.gov.in|access-date=2019-12-10|archive-date=2020-09-25|archive-url=https://web.archive.org/web/20200925124008/https://www.isro.gov.in/update/03-jun-2016/world%E2%80%99s-space-agencies-unite-to-face-climate-challenge|url-status=dead}}</ref> These scientists are increasingly concerned about the potential [[long-term effects of global warming]] on our natural environment and on the planet. Of particular concern is how [[climate change]] and global warming caused by [[human impact on the environment|anthropogenic]], or human-made releases of [[greenhouse gas]]es, most notably [[carbon dioxide]], can act interactively and have adverse effects upon the planet, its natural environment and humans' existence. It is clear the planet is warming, and warming rapidly. This is due to the [[greenhouse effect]], which is caused by greenhouse gases, which trap heat inside the Earth's atmosphere because of their more complex molecular structure which allows them to vibrate and in turn trap heat and release it back towards the Earth.<ref>{{Cite web|url=https://sites.google.com/view/climate-change-75518/home|title=Climate Change|website=sites.google.com|access-date=2019-01-08|archive-date=2023-02-17|archive-url=https://web.archive.org/web/20230217141640/https://sites.google.com/view/climate-change-75518/home|url-status=live}}</ref> This warming is also responsible for the extinction of natural habitats, which in turn leads to a reduction in wildlife population. The most recent report from the [[Intergovernmental Panel on Climate Change]] (the group of the leading climate scientists in the world) concluded that the earth will warm anywhere from 2.7 to almost 11 degrees Fahrenheit (1.5 to 6 degrees Celsius) between 1990 and 2100.<ref>{{cite web|last=Forthofer|first=Ron|title=It's Time To Act On Global Warming|url=http://www.commondreams.org/views01/0218-08.htm|publisher=Boulder Daily Camera|access-date=2013-10-28|url-status=dead|archive-url=https://web.archive.org/web/20130616203811/http://www.commondreams.org/views01/0218-08.htm|archive-date=2013-06-16}}</ref>
Efforts have been increasingly focused on the [[Mitigation of global warming|mitigation]] of greenhouse gases that are causing climatic changes, on [[Adaptation to global warming|developing adaptative strategies]] to global warming, to assist humans, other animal, and plant species, ecosystems, regions and [[nation]]s in adjusting to the [[effects of global warming]]. Some examples of recent collaboration to [[climate change mitigation|address climate change]] and global warming include:

[[File:Aletschgletsjer Zwitserland.JPG|right|thumb|Another view of the [[Aletsch Glacier]] in the [[Swiss Alps]], which because of [[global warming]] has been decreasing]]
* The [[United Nations Framework Convention on Climate Change|United Nations Framework Convention Treaty]] and convention on Climate Change, to stabilize greenhouse gas concentrations in the atmosphere at a level that would [[Avoiding dangerous climate change|prevent dangerous anthropogenic interference with the climate system]].<ref>[http://unfccc.int/2860.php United Nations Framework Convention on Climate Change] {{Webarchive|url=https://web.archive.org/web/20180201152427/http://unfccc.int/2860.php |date=2018-02-01 }} Retrieved August 2008.</ref>
* The [[Kyoto Protocol]], which is the protocol to the international Framework Convention on Climate Change treaty, again with the objective of reducing greenhouse gases in an effort to prevent anthropogenic climate change.<ref>[http://unfccc.int/resource/docs/convkp/kpeng.html Kyoto Protocol] {{Webarchive|url=https://web.archive.org/web/20090825212122/http://unfccc.int/resource/docs/convkp/kpeng.html |date=2009-08-25 }} from [http://unfccc.int/2860.php United Nations Framework Convention on Climate Change] {{Webarchive|url=https://web.archive.org/web/20180201152427/http://unfccc.int/2860.php |date=2018-02-01 }}, Retrieved August 2008.</ref>
* The [[Western Climate Initiative]], to identify, evaluate, and implement collective and cooperative ways to reduce greenhouse gases in the region, focusing on a market-based [[emissions trading|cap-and-trade]] system.<ref>[http://www.westernclimateinitiative.org/ Western Climate Initiative] {{Webarchive|url=https://web.archive.org/web/20080423080828/http://www.westernclimateinitiative.org/ |date=2008-04-23 }}, Retrieved on Feb 12, 2009.</ref>

A significantly profound challenge is to identify the natural environmental dynamics in contrast to environmental changes not within natural variances. A common solution is to adapt a static view neglecting natural variances to exist. Methodologically, this view could be defended when looking at processes which change slowly and short time series, while the problem arrives when fast processes turns essential in the object of the study.

===Climate===
[[File:ClimateMap World.png|alt=Map of world dividing climate zones, largely influenced by latitude. The zones, going from the equator upward (and downward) are Tropical, Dry, Moderate, Continental and Polar. There are subzones within these zones.|thumb|left|{{center|Worldwide [[climate]] classifications map}}]]
{{Main|Climate}}

[[Climate]] looks at the statistics of [[temperature]], [[humidity]], [[atmospheric pressure]], [[wind]], [[rainfall]], atmospheric particle count and other [[Meteorology|meteorological]] elements in a given region over long periods of time.<ref name="ncei.noaa.gov">{{Cite web|date=2018-03-09|title=What's the Difference Between Weather and Climate?|url=http://www.ncei.noaa.gov/news/weather-vs-climate|access-date=2021-04-22|website=National Centers for Environmental Information (NCEI)|language=en|archive-date=2021-04-22|archive-url=https://web.archive.org/web/20210422024942/https://www.ncei.noaa.gov/news/weather-vs-climate|url-status=live}}</ref> [[Weather]], on the other hand, is the present condition of these same elements over periods up to two weeks.<ref name="ncei.noaa.gov"/>

Climates can be [[Climate classification|classified]] according to the average and typical ranges of different variables, most commonly temperature and precipitation. The most commonly used classification scheme is the one originally developed by [[Wladimir Köppen]]. The [[Thornthwaite climate classification|Thornthwaite system]],<ref>{{cite journal|last1=Thornthwaite|first1=C. W.|title=An Approach toward a Rational Classification of Climate|journal=Geographical Review|volume=38|issue=1|year=1948|pages=55–94|jstor=210739|doi=10.2307/210739|bibcode=1948GeoRv..38...55T }}</ref> in use since 1948, uses [[evapotranspiration]] as well as temperature and precipitation information to study animal species diversity and the potential impacts of [[climate change]]s.<ref>{{Cite book|url=https://books.google.com/books?id=gCs5DwAAQBAJ&pg=PA89|title=English for geographers|last=García|first=Carmen Isabel Luján|date=2013-06-19|publisher=Editorial Club Universitario|isbn=9788499485676}}</ref>

===Weather===
[[File:Rainbow over Bristol.jpg|thumb|right|A [[rainbow]] is an [[optics|optical]] and [[meteorology|meteorological]] phenomenon that causes a [[optical spectrum|spectrum]] of [[light]] to appear in the sky when the Sun shines onto droplets of moisture in the [[Earth's atmosphere]].]]
{{Main|Weather}}
[[Weather]] is a set of all the [[Phenomenon|phenomena]] occurring in a given [[atmosphere|atmospheric]] area at a given [[time]].<ref>Merriam-Webster Dictionary. [http://www.merriam-webster.com/dictionary/weather Weather.] {{Webarchive|url=https://web.archive.org/web/20170709032002/https://www.merriam-webster.com/dictionary/weather |date=2017-07-09 }} Retrieved on 2008-06-27.</ref> Most weather phenomena occur in the [[troposphere]],<ref>Glossary of Meteorology. [http://amsglossary.allenpress.com/glossary/search?p=1&query=hydrosphere&submit=Search Hydrosphere.] {{webarchive|url=https://web.archive.org/web/20120315161323/http://amsglossary.allenpress.com/glossary/search?p=1&query=hydrosphere&submit=Search |date=2012-03-15 }} Retrieved on 2008-06-27.</ref><ref name="trop">Glossary of Meteorology. [http://amsglossary.allenpress.com/glossary/browse?s=t&p=51 Troposphere.] {{webarchive|url=https://web.archive.org/web/20120928061111/http://amsglossary.allenpress.com/glossary/browse?s=t&p=51 |date=2012-09-28 }} Retrieved on 2008-06-27.</ref> just below the [[stratosphere]]. Weather refers, generally, to day-to-day temperature and precipitation activity, whereas [[climate]] is the term for the average atmospheric conditions over longer periods of time.<ref>{{cite encyclopedia | title = Climate | encyclopedia = Glossary of Meteorology | publisher = [[American Meteorological Society]] | url = http://amsglossary.allenpress.com/glossary/search?id=climate1 | access-date = 2008-05-14 }}</ref> When used without qualification, "weather" is understood to be the weather of Earth.

Weather occurs due to density (temperature and moisture) differences between one place and another. These differences can occur due to the sun angle at any particular spot, which varies by latitude from the tropics. The strong temperature contrast between polar and tropical air gives rise to the [[jet stream]]. Weather systems in the [[mid-latitudes]], such as [[extratropical cyclone]]s, are caused by instabilities of the jet stream flow. Because the Earth's [[Earth's rotation|axis]] is tilted relative to its orbital plane, [[sunlight]] is incident at different angles at different times of the year. On the Earth's surface, temperatures usually range ±40&nbsp;°C (100&nbsp;°F to −40&nbsp;°F) annually. Over thousands of years, changes in the Earth's orbit have affected the amount and distribution of solar energy received by the Earth and influenced long-term climate.

Surface [[temperature]] differences in turn cause pressure differences. Higher altitudes are cooler than lower altitudes due to differences in compressional heating. Weather forecasting is the application of science and technology to predict the state of the [[Earth's atmosphere|atmosphere]] for a future time and a given location. The [[Earth's atmosphere|atmosphere]] is a [[chaos theory|chaotic system]], and small changes to one part of the system can grow to have large effects on the system as a whole. Human attempts to [[weather control|control the weather]] have occurred throughout human history, and there is evidence that civilized human activity such as [[agriculture]] and [[Industrial society|industry]] has inadvertently modified weather patterns.

==Life==
[[File:Diversity of plants image version 5.png|thumb|left|{{center|There are many [[plant species]] on the planet.}}]]
[[File:Animal diversity.png|thumb|right|{{center|An example of the many [[animal species]] on the Earth}}]]
{{Main|Life|Biology|Biosphere}}

Evidence suggests that [[life|life on Earth]] has existed for about 3.7 [[1000000000 (number)|billion]] years.<ref>"[http://www.ucmp.berkeley.edu/exhibits/historyoflife.php History of life through time] {{Webarchive|url=https://web.archive.org/web/20150503174117/http://www.ucmp.berkeley.edu/exhibits/historyoflife.php |date=2015-05-03 }}". University of California Museum of Paleontology.</ref> All known life forms share fundamental molecular mechanisms, and based on these observations, theories on the origin of life attempt to find a mechanism explaining the formation of a primordial single cell organism from which all life originates. There are many different hypotheses regarding the path that might have been taken from simple [[organic molecule]]s via pre-cellular life to protocells and metabolism.

Although there is no universal agreement on the definition of life, scientists generally accept that the biological manifestation of life is characterized by [[Organism|organization]], [[metabolism]], [[cell growth |growth]], [[adaptation]], response to [[stimulus (physiology)|stimuli]] and [[reproduction]].<ref>{{cite web|year=2006 |url=http://www.calacademy.org/exhibits/xtremelife/what_is_life.php |title= Definition of Life |publisher=California Academy of Sciences |access-date=2007-01-07 |url-status=dead |archive-url=https://web.archive.org/web/20070208220940/http://www.calacademy.org/exhibits/xtremelife/what_is_life.php |archive-date=2007-02-08 }}</ref> Life may also be said to be simply the characteristic state of [[organism]]s. In [[biology]], the science of living organisms, "life" is the condition which distinguishes active [[organism]]s from [[Inorganic compound|inorganic matter]], including the capacity for growth, [[Physiology|functional activity]] and the continual change preceding death.<ref name="ReferenceA">The Concise Oxford Dictionary. English Edition 1991{{full citation needed|date=January 2024}}</ref><ref name="Merriam-Webster Dictionary">{{cite web |url=http://www.merriam-webster.com/dictionary/life |title=Merriam-Webster Dictionary |access-date=2009-06-21 |publisher=Merriam-Webster Dictionary |archive-date=2021-12-13 |archive-url=https://web.archive.org/web/20211213211541/https://www.merriam-webster.com/dictionary/life |url-status=live }}</ref>

A diverse variety of living organisms (life forms) can be found in the [[biosphere]] on Earth, and properties common to these organisms—plants, [[animal]]s, [[fungus|fungi]], [[protist]]s, [[archaea]], and [[bacteria]]—are a [[Carbon-based life|carbon]]- and water-based [[Cell (biology)|cellular]] form with complex [[organization]] and heritable [[gene]]tic information. Living organisms undergo [[metabolism]], maintain [[homeostasis]], possess a capacity to [[Cell growth|grow]], respond to [[Stimulus (physiology)|stimuli]], [[reproduce]] and, through [[natural selection]], adapt to their environment in successive generations. More complex living organisms can communicate through various means.

==Ecosystems==
[[File:River gambia Niokolokoba National Park.gif|thumb|left|[[Rainforest]]s often have a great deal of [[biodiversity]] with many plant and animal species. This is the [[Gambia River]] in [[Senegal]]'s [[Niokolo-Koba National Park]].]]
{{Main|Ecosystem}}

An [[ecosystem]] (also called an environment) is a natural unit consisting of all plants, animals, and micro-organisms ([[biotic component|biotic]] factors) in an area functioning together with all of the non-living physical ([[abiotic]]) factors of the environment.<ref>{{cite book |first=Robert W. |last=Christopherson |year=1996 |title=Geosystems: An Introduction to Physical Geography |publisher=Prentice Hall |isbn=0-13-505314-5 }}</ref>

Central to the ecosystem concept is the idea that [[living organism]]s are continually engaged in a highly interrelated set of relationships with every other element constituting the [[environment (biophysical)|environment]] in which they exist. [[Eugene Odum]], one of the founders of the science of [[ecology]], stated: "Any unit that includes all of the organisms (i.e.: the "community") in a given area interacting with the physical environment so that a flow of energy leads to clearly defined trophic structure, biotic diversity, and material cycles (i.e.: exchange of materials between living and nonliving parts) within the system is an ecosystem."<ref>{{cite book |last=Odum |first=E. P. |year=1971 |title=Fundamentals of Ecology |url=https://archive.org/details/fundamentalsofec0000odum |url-access=registration |edition=Third |publisher=Saunders |location=New York |isbn=0-7216-6941-7 }}</ref>

[[File:Creek and old-growth forest-Larch Mountain.jpg|thumb|right|[[Old-growth forest]] and a [[creek (tidal)|creek]] on [[Larch Mountain (Multnomah County, Oregon)|Larch Mountain]], in the U.S. state of [[Oregon]]]]

The human ecosystem concept is then grounded in the deconstruction of the human/nature [[dichotomy]], and the emergent premise that all species are ecologically integrated with each other, as well as with the abiotic constituents of their [[biotope]].

A more significant number or variety of species or [[Biodiversity|biological diversity]] of an ecosystem may contribute to greater resilience of an ecosystem because there are more species present at a location to respond to change and thus "absorb" or reduce its effects. This reduces the effect before the ecosystem's structure changes to a different state. This is not universally the case and there is no proven relationship between the species diversity of an ecosystem and its ability to provide goods and services on a sustainable level.

The term ecosystem can also pertain to human-made environments, such as [[human ecosystem]]s and human-influenced ecosystems. It can describe any situation where there is relationship between living organisms and their environment. Fewer areas on the surface of the earth today exist free from human contact, although some genuine [[wilderness]] areas continue to exist without any forms of human intervention.
{{clear}}

==Biogeochemical cycles==
[[File:Plagiomnium affine laminazellen.jpeg|thumb|[[Chloroplast]]s conduct [[photosynthesis]] and are found in [[plant cell]]s and other [[eukaryote|eukaryotic]] organisms. These are chloroplasts visible in the cells of ''Plagiomnium affine'' — many-fruited thyme-moss.]]
{{Main|Biogeochemical cycles}}

Global [[biogeochemical cycle]]s are critical to life, most notably those of [[water]], [[oxygen]], [[carbon]], [[nitrogen]] and [[phosphorus]].<ref>Smil, V. (2000). ''Cycles of Life''. New York: Scientific American Library. {{ISBN|978-0-7167-5079-6}}.</ref>
* The [[nitrogen cycle]] is the transformation of nitrogen and nitrogen-containing compounds in nature. It is a cycle which includes gaseous components.
* The [[water cycle]], is the continuous movement of water on, above, and below the surface of the Earth. Water can change states among liquid, vapour, and ice at various places in the water cycle. Although the balance of water on Earth remains fairly constant over time, individual water molecules can come and go.
* The [[carbon cycle]] is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the Earth.
* The [[oxygen cycle]] is the movement of oxygen within and between its three main reservoirs: the atmosphere, the biosphere, and the [[lithosphere]]. The main driving factor of the oxygen cycle is [[photosynthesis]], which is responsible for the modern Earth's atmospheric composition and life.
* The [[phosphorus cycle]] is the movement of phosphorus through the lithosphere, hydrosphere, and biosphere. The atmosphere does not play a significant role in the movements of phosphorus, because phosphorus and phosphorus compounds are usually solids at the typical ranges of temperature and pressure found on Earth.

==Wilderness==
[[File:Swiss National Park 131.JPG|thumb|left|A [[Temperate coniferous forest|conifer forest]] in the [[Swiss Alps]] ([[Swiss National Park|National Park]])]]
[[File:Togiak Wilderness.jpg|thumb|The [[Ahklun Mountains]] and the [[Togiak Wilderness]] within the [[Togiak National Wildlife Refuge]] in the U.S. state of [[Alaska]]]]
{{Main|Wilderness}}

[[Wilderness]] is generally defined as a natural environment on Earth that has not been significantly modified by [[human]] activity. The [[WILD Foundation]] goes into more detail, defining wilderness as: "The most intact, undisturbed wild natural areas left on our planet – those last truly wild places that humans do not control and have not developed with roads, pipelines or other industrial infrastructure."<ref>{{cite web |url=http://www.wild.org/main/about/what-is-a-wilderness-area/ |title=The WILD Foundation |publisher=Wild.org |access-date=2013-03-09 |url-status=dead |archive-url=https://archive.today/20121204162126/http://www.wild.org/main/about/what-is-a-wilderness-area/ |archive-date=2012-12-04 }}</ref> Wilderness areas and protected [[parks]] are considered important for the survival of certain [[species]], ecological studies, [[Habitat conservation|conservation]], solitude, and [[recreation]]. Wilderness is deeply valued for cultural, spiritual, [[moral]], and [[aesthetic]] reasons. Some nature writers believe wilderness areas are vital for the human spirit and creativity.<ref>{{cite book|author1=Botkin, Daniel B.|title=No Man's Garden: Thoreau And A New Vision For Civilization And Nature|url=https://books.google.com/books?id=OvF40zunJR4C|year=2001|publisher=Island Press|isbn=978-1-55963-465-6|pages=155–157}}</ref>

The word, "wilderness", derives from the notion of [[wildness]]; in other words that which is not controllable by humans. The word [[etymology]] is from the [[Old English]] ''wildeornes'', which in turn derives from ''wildeor'' meaning ''wild beast'' (wild + deor = beast, deer).<ref>[http://www.collinsdictionary.com/dictionary/english/wilderness wilderness] {{Webarchive|url=https://web.archive.org/web/20121020194038/http://www.collinsdictionary.com/dictionary/english/wilderness |date=2012-10-20 }}. CollinsDictionary.com. Collins English Dictionary – Complete & Unabridged 11th Edition. Retrieved November 29, 2012.</ref> From this point of view, it is the wildness of a place that makes it a wilderness. The mere presence or activity of people does not disqualify an area from being "wilderness". Many ecosystems that are, or have been, inhabited or influenced by activities of people may still be considered "wild". This way of looking at wilderness includes areas within which natural processes operate without very noticeable human interference.

[[Wildlife]] includes all non-[[domesticated]] plants, animals and other organisms. Domesticating wild plant and animal species for human benefit has occurred many times all over the planet, and has a major impact on the environment, both positive and negative. Wildlife can be found in all ecosystems. Deserts, rain forests, plains, and other areas—including the most developed [[Urban area|urban]] sites—all have distinct forms of wildlife. While the term in popular culture usually refers to animals that are untouched by civilized human factors, most scientists agree that wildlife around the world is (now) impacted by human activities.

[[File:Ahja jõe ürgorg.jpg|thumb|center|upright=4.1|{{center|A view of [[wilderness]] in Estonia}}]]

==Challenges==
<!-- Images -->
[[File:Air pollution by industrial chimneys.jpg|thumb|right|Before [[flue-gas desulfurization]] was installed, the [[air pollution|air-polluting]] emissions from this power plant in [[New Mexico]] contained excessive amounts of [[sulfur dioxide]].]]
[[File:Amazon Rainforest-bird site.jpg|thumb|[[Amazon rainforest]] in [[Brazil]]. The tropical rainforests of South America contain the largest diversity of species on Earth, including some that have evolved within the past few hundred thousand years.<ref>{{cite web|url=http://earthobservatory.nasa.gov/Newsroom/view.php?id=28907 |title=Why the Amazon Rainforest is So Rich in Species : News |publisher=Earthobservatory.nasa.gov |date=2005-12-05 |access-date=2013-03-09 |url-status=dead |archive-url=https://web.archive.org/web/20110225204348/http://earthobservatory.nasa.gov/Newsroom/view.php?id=28907 |archive-date=2011-02-25 }}</ref><ref>{{cite web |url=https://www.sciencedaily.com/releases/2005/12/051205163236.htm |title=Why The Amazon Rainforest Is So Rich In Species |publisher=Sciencedaily.com |date=2005-12-05 |access-date=2013-03-09 |archive-date=2019-07-14 |archive-url=https://web.archive.org/web/20190714220011/https://www.sciencedaily.com/releases/2005/12/051205163236.htm |url-status=live }}</ref>]]
<!-- Images End -->

{{See also|List of environmental issues|World Scientists' Warning to Humanity}}
It is the common understanding of ''natural environment'' that underlies [[environmentalism]] — a broad [[politics|political]], [[sociology|social]] and [[philosophy|philosophical]] movement that advocates various actions and policies in the interest of protecting what nature remains in the natural environment, or restoring or expanding the role of nature in this environment. While true wilderness is increasingly rare, ''wild'' nature (e.g., unmanaged [[forests]], uncultivated [[grasslands]], [[wildlife]], [[wildflower]]s) can be found in many locations previously inhabited by humans.

Goals for the benefit of people and natural systems, commonly expressed by [[environmental scientist]]s and [[environmentalist]]s include:
* Elimination of [[pollution]] and [[toxicant]]s in air, water, soil, buildings, manufactured goods, and food.
* Preservation of [[biodiversity]] and protection of [[endangered species]].
* [[Conservation movement|Conservation]] and [[sustainable use]] of resources such as [[water]],<ref>{{Cite journal|author1=Escolero, O. |author2=Kralisch, S. |author3=Martínez, S.E. |author4=Perevochtchikova, M.|year=2016|title=Diagnóstico y análisis de los factores que influyen en la vulnerabilidad de las fuentes de abastecimiento de agua potable a la Ciudad de México, México|journal=Boletín de la Sociedad Geológica Mexicana|language=es|volume=68|issue=3|pages=409–427|doi=10.18268/BSGM2016v68n3a3 |doi-access=free}}</ref> land, air, energy, raw materials, and natural resources.
* Halting human-induced [[global warming]], which represents pollution, a threat to biodiversity, and a threat to human populations.
* Shifting from [[fossil fuels]] to [[renewable energy]] in electricity, heating and cooling, and transportation, which addresses pollution, global warming, and sustainability. This may include [[public transportation]] and [[distributed generation]], which have benefits for traffic congestion and electric reliability.
* Shifting from meat-intensive diets to largely [[plant-based diets]] in order to help mitigate [[biodiversity loss]] and climate change.<ref>{{cite news|last=Drayer|first=Lisa|date=January 2, 2019|title=Change your diet to combat climate change in 2019|url=https://www.cnn.com/2018/10/18/health/plant-based-diet-climate-change-food-drayer/index.html|work=CNN|access-date=February 14, 2019|archive-date=February 13, 2019|archive-url=https://web.archive.org/web/20190213222306/https://www.cnn.com/2018/10/18/health/plant-based-diet-climate-change-food-drayer/index.html|url-status=live}}</ref>
* Establishment of [[nature reserve]]s for recreational purposes and ecosystem preservation.
* Sustainable and less polluting [[waste management]] including [[waste reduction]] (or even [[zero waste]]), [[reuse]], [[recycling]], [[composting]], [[waste-to-energy]], and [[anaerobic digestion]] of sewage sludge.
* Reducing [[overconsumption|profligate consumption]] and clamping down on [[illegal, unreported and unregulated fishing|illegal fishing]] and [[Illegal logging|logging]].<ref>{{cite news|last=Plumer|first=Brad|date=May 6, 2019|title=Humans Are Speeding Extinction and Altering the Natural World at an 'Unprecedented' Pace|url=https://www.nytimes.com/2019/05/06/climate/biodiversity-extinction-united-nations.html|work=[[The New York Times]]|access-date=June 14, 2019|archive-date=June 14, 2019|archive-url=https://web.archive.org/web/20190614201836/https://www.nytimes.com/2019/05/06/climate/biodiversity-extinction-united-nations.html|url-status=live}}</ref>
* Slowing and stabilisation of [[human population growth]].<ref>{{cite journal|vauthors=Ripple WJ, Wolf C, Newsome TM, Galetti M, Alamgir M, Crist E, Mahmoud MI, Laurance WF|title=World Scientists' Warning to Humanity: A Second Notice|journal=[[BioScience]]|volume=67|issue=12|pages=1026–1028|date=13 November 2017|doi=10.1093/biosci/bix125|quote=It is also time to re-examine and change our individual behaviors, including limiting our own reproduction (ideally to replacement level at most)...|doi-access=free|hdl=11336/71342|hdl-access=free}}</ref>
* Reducing the import of second hand electronic appliances from developed countries to developing countries.<ref>{{Cite news |date=2019-05-29 |title=The Rich World's Electronic Waste, Dumped in Ghana |language=en |work=Bloomberg.com |url=https://www.bloomberg.com/news/articles/2019-05-29/the-rich-world-s-electronic-waste-dumped-in-ghana |access-date=2023-05-06 |archive-date=2023-04-16 |archive-url=https://web.archive.org/web/20230416041601/https://www.bloomberg.com/news/articles/2019-05-29/the-rich-world-s-electronic-waste-dumped-in-ghana |url-status=live }}</ref><ref>{{Cite web |title=India: E-waste provides poor children a dangerous living – DW – 02/09/2023 |url=https://www.dw.com/en/india-electronic-waste-provides-poor-children-a-dangerous-living/a-64656699 |access-date=2023-05-06 |website=dw.com |language=en |archive-date=2023-05-06 |archive-url=https://web.archive.org/web/20230506023312/https://www.dw.com/en/india-electronic-waste-provides-poor-children-a-dangerous-living/a-64656699 |url-status=live }}</ref>

==Criticism==
In some cultures the term environment is meaningless because there is no separation between people and what they view as the natural world, or their surroundings.<ref>Jamieson, Dale. (2007). "The Heart of Environmentalism". In R. Sandler & P. C. Pezzullo. ''Environmental Justice and Environmentalism''. Massachusetts Institute of Technology Press. pp. 85–101. {{ISBN|9780262195522}}</ref> Specifically in the United States and Arabian countries many native cultures do not recognize the "environment", or see themselves as environmentalists.<ref>Davis, T. (2000). ''Sustaining the Forest, the People, and the Spirit. State University of New York''. pp. 1–24. {{ISBN|9780791444153}}</ref>

==See also==
{{portal|Environment|Ecology|Plants|Trees|Water|World}}
{{Div col|colwidth=30em}}
* [[Biophilic design]]
* [[Citizen's dividend]]
* [[Conservation movement]]
* [[Environmental history of the United States]]
* [[Gaia hypothesis]]
* [[Geological engineering]]
* [[Green exercise]]
* [[Greening]]
* [[Index of environmental articles]]
* [[List of conservation topics]]
* [[List of environmental books]]
* [[List of environmental issues]]
* [[List of environmental websites]]
* [[Natural capital]]
* [[Natural history]]
* [[Natural landscape]]
* [[Nature-based solutions]]
* [[Political representation of nature]]
* [[Sustainability]]
* [[Sustainable agriculture]]
* [[Timeline of environmental history]]
* [[Urban reforestation]]
{{div col end}}

==References==
{{reflist|30em}}

==Further reading==
<div style="font-size:97%;">
* {{cite book|title=Earth Science: An illustrated guide to science|first=Simon|last=Adams|author2=David Lambert|publisher=Chelsea House|location=New York NY 10001|year=2006|page=20|isbn=0-8160-6164-5}}

* Allaby, Michael, and Chris Park, eds. ''A dictionary of environment and conservation'' (Oxford University Press, 2013), with a British emphasis.
* {{cite web|url=http://okfirst.mesonet.org/train/meteorology/EnergyBudget.html|title=Earth's Energy Budget|date=1996–2004|access-date=2007-11-17|publisher=Oklahoma Climatological Survey}}
* {{cite book|title=Earth Cycles: A historical perspective|first=David|last=Oldroyd|publisher=Greenwood Press|location=Westport, Connicticut|year=2006|isbn=0-313-33229-0}}
* {{cite web|url=http://www.ucmp.berkeley.edu/geology/tecmech.html|title=The mechanism behind plate tectonics|date=2007-02-05|access-date=2007-11-17|author=Simison, W. Brian}}
* {{cite book|title=How Does the Earth Work? Physical Geology ''and the'' Process of Science|first=Gary A.|last=Smith|author2=Aurora Pun|publisher=Pearson Prentice Hall|location=Upper Saddle River, NJ 07458|year=2006|page=5|isbn=0-13-034129-0}}</div>
* {{cite book|last=Miller|first=G. Tyler|title=Environmental science|publisher=[[Cengage Learning#Brands.2Fimprints|Wadsworth]]|year=1995|location=California|url=https://archive.org/details/environmentalsci0000mill_5thEd.|isbn=0-534-21588-2|url-access=registration}}
* {{cite journal
  |last = McCallum
  |first = Malcolm L.
  |author2=Gwendolynn W. Bury
  |title = Google search patterns suggest declining interest in the environment.
  |journal = Biodiversity and Conservation
  |year = 2013
 |volume = 22
 |issue = 6–7
 |pages = 1355–1367
 |doi = 10.1007/s10531-013-0476-6|bibcode = 2013BiCon..22.1355M
 |s2cid = 15593201
 }}

==External links==
{{Wiktionary}}
* {{Commons category-inline|Environment}}
* [http://www.unep.org/ UNEP - United Nations Environment Programme]
* [http://www.bbc.co.uk/sn/ BBC - Science and Nature].
* [https://web.archive.org/web/20090506215842/http://science.gov/browse/w_123.htm Science.gov – Environment & Environmental Quality]

{{Earth}}
{{Environmental science}}
{{Nature nav}}

{{Authority control}}

[[Category:Natural environment| ]]
[[Category:Habitat]]
[[Category:Earth]]